Track laying front wheel for tricycle tractors



Jan. 5, 1954 J, MILLER 2,665,175

TRACK LAYING FRONT WHEEL FOR TRICYCLE TRACTORS Filed May 17, 1952 2 Sheets-Sheet l I N VEN TOR.

AND 1%, ATTORM Y5 Jan. 5, 1954 R. J. MILLER TRACK LAYING FRONT WHEEL FOR .TRICYCLE TRACTORS 2 Sheets-Sheet 2 Filed May 17, 1952 1N VEN TOR. FAX/WWO J 44/115? BY Am ATTOR Z EYS Patented Jan. 5, 1954 'rii'is"'invent-i-bn relates d atricycle' -front vrheel attachment we 'c'onvementiyeonverting agricuhtur'al tractors orths rdawwheertypeao a 'tricycle having a central front, steerable, ground n-g-ag=="- ing elernent."

Whil'it is recognized that afour Wheel tractor 1 provides the iit-fnost in stability and maneuver: ability forheavy tillage operations, there-isaways re'cogmzeaneed fiSr' a tri'cycle type-nae ground engaging element to bett'ei"*-"adapt* the' tractor for cultivating operations and similar o erations-'wherein the tractor 'must' 'pass-through ro'vvs"'of--'-grovviiig'" cro s? Accordingly; there -ha's be'en a "definiteneedfor-an economicalfront-i onve'ntional' fou'r wheettractor: to convert suchinto' a tricycle or-"cultivating typ'e=of tractor:

StilL-an'othr obJc't ofthis inventioni'is to pro Vid a steerable 'endless blt bogie to funtion' as' the str'able 'grounaengagmg: element row the front end of a tractor. I

The 'specific nature ofi this invention, as well as other objects and advantages thereof, will become apparent "to those skilled in'the' art from the following detail'ed fie'scriptioh"taken in conjunc- 40 tion with the attached drawingson which, by way of prefe'rredexarnple only, is-il1ustrated two embodiments-of this invention.

Onthe drawings:

3" Figure 1 i's-a: side elevational view of a convene? tional tractor having.la front-steering element embodying this invention assembled thereto;

Figure"? is an enlarged-scale side elevational vi'w'"of thefront"end of'the tractor of Figure "1 with portions thereof broken away for clarity of illustration;

Figure 3 is a front elevational View of the endless belt steerable bogie embodying this invention;

Fig'ure tis anenlarged scale sectional view taken on the'plane' A t "of Figure'Z;

Figurefi 'is a fr'ont elevati'onal view of a modi fied"pu1l'ey' construction.

As shown 'ohthdrawi'ngs:

'pair of laterally spacediront wheels (not shown) whichare ste'ered' bya steering wheell 0a operat ing threug'ha' suitable steering gear (notshowrr) and steering-crank arm's! 0b and radius rods 1 ea Such 'tra'ctor is als'd conventionally provided with" a vertical mounting face la-at th'elower forward edge of the tractor engi-ne housing H.

In accordance with this invention, the conven-- tional-front axle m'ounting'"bracket which ordi narily -isboltecl to the'moun'ting -fiange Ha is"- enti're'ly removed and 'a -'specially constructed housing I 2 is provided in itspl'ace; 'sueh housinghaving a face [2a at the rear end thereof shaped" to'abiita'nd conform'to the tractor engine mount-'- ing fde ll (1 ans "s't'flllralbl-'tl'lefi'n'j T plurality of -"bolts l I b Tli housing l 2 -is *provided atits front end ith a bracket portion" I25 which is ,as iridicated at l 2a," to receive the bolts which conventidnally supportthe sheet I metal apftlil cured te ms side of gear chamber- Rd in horizontal' tr'ansverse relationshipand a shaft I4 is* journa'ledin bus'hi'ng I2 and projects" into the interiorof gear chamber Inf-where it mounts crank-'ai irris "connected by cohventional ball joint I622 to the -end ofthe drag' link'lilc of the con-- ventional tractor steering mechanism; The drag lirik'normaliyprdvidd 'bn"the opposite side of the tractor-is removed."

'I'lie bottom -wall of"gea-r* chamber Ed is pro viddwi-th ayertieal'bore [2e in'whi'ch is mounted suitableantii rictionbeaiing elements 1 3' to jcurnal a=stub shaft liif Thetop 'en'dof 'stub shaft lfl 'hal's" a=--beve1- ;gear I 9" secured thereto which air-the ector'bevel gear [5. The-lower" 8 isrigidly secured to'an in verted u shaped supp'orting yoke "2%? which has vertical arms 20c and 20a, mounting' 'an endless-* belt type bogie unit 2| constructed in accordance with this invention.

The bogie unit 2| comprises a pair of laterally spaced, longitudinally extending sill members 22 MWWMMNWWWWWW which have mounted therebetween in transverse relationship a front pulley shaft 24 and a rear pulley shaft 25. The sill members are respectively pivotally supported on the depending arms of yoke 20 by bearing bushings 20a and retaining bolts 201) so that the entire bogie unit 2| can pivot in a longitudinal vertical plane with respect to the tractor. Suitable stops 20c are rigidly attached to each of the depending arms 20c and 20d of yoke 20 to limit both the clockwise and counterclockwise range of pivotal movement of the sills 22.

The shafts 2t and 25 respectively mount drumlike pulley elements 23 and 2?, each of which is provided with a plurality of laterally spaced V-grooves 26a and 27a. At the front end of each of the sills 22 a forwardly and upwardly projecting bracket 22a is provided and such bracket in turn has a pair of longitudinally spaced, laterally projecting ears 22b and 220 formed thereon. A rod-like support 28 is slidably mounted in suitable aligned holes provided on the cars 2212 and 220 and such support rods are resiliently biased in a forward direction by springs 28 which respectively surround the rods 23 and operate between the ears 2% and a washer 23a secured to the rod 28 by a transverse pin 28b. The forward ends of each of the rods 28 defines an eye portion 280 between which is mounted an idler pulley shaft 30. A drum-like idler pulley 3! having a plurality of laterally spaced l-grooves 35a formed thereon is mounted on idler pulley shaft 30. A plurality of V-belts 32 are then mounted in surrounding relationship to the pulleys 23 and 2'? and 3! and are respectively disposed in the v-grooves 25a, Zia, and Sic. The bottom flights of the V-belts 32 which are disposed between the pulleys 25 and 2'! normally provide a ground engaging element and all of the belts 32 are maintained in a tensioned condition through the biaslng action of the springs Ell operating on the idler pulley 3|.

In Figure 6 there is shown a modified pulley construction. Such modification comprises mounting a pair of identical pulleys 33 on the shaft 24 between the sills 22. The pulleys 33, of the same diameter as pulleys 26, are respectively provided with laterally spaced V- grooves 33a. Pulleys 33 are transversely separated by an antifriction washer 33b. When using the pulley construction shown in Figure 6, it will, of course, be necessary to replace the pulleys 21 and 3! with a paired pulley arrangement similar to pulleys 33. As such pulley arrangements, however, are identical to that shown in Figure 6, further description is not believed necessary. The V-belts 32 are trained over pulleys 33 within the V-grooves 33a and the other pulleys (not shown) which correspond to pulleys 21 and 3!.

When the bogie unit is equipped with pulleys constructed in accordance with the modification shown in Figure 6, the steerability of such unit is somewhat improved. As the bogie unit is turned about its vertical axis, the lateral displacement of such unit causes the inner set of V-belts 32 on the inner set of pulleys nearest to the center of the radius of the turn to revolve at a slower rate than the outer set of belts and pulleys. This differential action thereby facilitates turning of the bogie unit.

The forward and upward inclination of that portion of the flights of the belts 32 lying between the idler pulley 2| and ground pulley 26, coupled with the fact that the entire bogie unit 2! pivot in a longitudinal vertical plane with re' spect to the tractor, permits the bogie unit 21 to traverse rough terrain without excessive power consumption. Furthermore, due to the number of belts 32 provided and their lateral spacing, it is apparent that there is a large surface area of the endless belt bogie unit always in engagement with the ground, and hence, even in the soft or sandy soils, there will be far less tendency of the bogie unit to sink into the ground than would be encountered with any conventional wheel.

From the foregoing description, it is apparent that this invention provides a single front steerable supporting element which may be conveniently applied to conventional types of four wheel tractors. Furthermore, the bogie unit provided by this invention permits effective steering of the tractor to be accomplished over rough terrain or soft ground with minimum energy requirements.

It will of course, be understood that many details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claim.

I claim:

An endless track wheel for tractors comprising a frame structure including a pair of laterally spaced, longitudinal frame sills, a pair of axles mounted between said frame sills in longitudinally spaced relation, a plurality of V-belt pulley structures respectively journalled on each axle with their pulley grooves in axial alignment, a plurality of V-belts respectively entrained around said pulley structures, a pair of brackets respectively secured to said frame sills in forwardly and upwardly projecting relationship, a pair of laterally outwardly projecting, longitudinally spaced ears on each bracket, said ears having longitudinally aligned holes therein, a rod slidably journalled in each pair of holes, a transverse axle carried by the forward ends of said rods, a plurality of V-belt idler pulleys journalled on said axle and respectively engageable with said V- belts, a spring seat secured to each rod at a point intermediate said ears, and a compression spring surrounding each rod and operating between said spring seat and the rearmost ear to urge the corresponding rod forwardly, thereby tensioning said V-belts.

RAYMOND J. MILLER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,277,855 Mercier Mar. 31, 1942 2,301,152 Strehlow Nov. 3, 1942 2,416,679 Curtis Mar. 4, 1947 2,613,892 Dever Oct. 14, 1952 FOREIGN PATENTS Number Country Date 980,237 France i- Dec. 20, 1950 

